Newbury Spa on 11th or 12th ave and Oasis on 17th ave sw are the ones my girlfriend frequents outside of Stillwater.
Depends what she wants at the spa... Newbury is good for manicures, pedicures, etc. and has Crave cupcakes for patrons to enjoy.
Oasis is better for massages if she asks for Jeff - apparently he was the masseuse for Yelle when he played here in Calgary.